We study voltage driven translocation of a single stranded DNA through a membrane channel. Our model, based on a master equation approach, investigates the probability density function of the translocation times, and shows that it can be either double peaked or mono peaked, depending on the system parameters. We show that the most probable translocation time is proportional to the polymer lengt...

new nanosystems as well as new technologies for their preparation. Polymer nanofibers prepared by the electrospinning method are just one of such examples. These are solid fibers with diameters from a few tens up to 1000 nm (Fig. 1) and theoretically unlimited length having a huge surface area per unit mass and small pore size. All these parameters strongly depend on the preparation process and...

Soil consolidation as the dissipation of excess pore water pressure is mainly affected by the relative hydraulic conductivity among the layers. Geostatistical parameters such as the mean, the standard deviation, and the correlation length are physical indicators for each sedimentation and formation history. The effects of spatial variability on the excessive pore water pressure dissipation duri...

Electrochemical capacitors with fast charging-discharging rates are very promising for hybrid electric vehicle industries including portable electronics. Complicated pore structures have been implemented in active materials to increase energy storage capacity, which often leads to degrade dynamic response of ions. In order to understand this trade-off phenomenon, we report a theoretical model b...

Large-mesopore silica films with a narrow pore size distribution and high porosity have been obtained by a sol-gel reaction of a silicon oxide precursor (TEOS) and using polystyrene-block-poly(ethylene oxide) (PS-b-PEO) copolymers as templates in an acidic environment. PS-b-PEO copolymers with different molecular weight and composition have been studied in order to assess the effects of the blo...

A set of computationally generated granular packings of frictionless grains is statistically analyzed using tools from stochastic geometry. We consider both the graph of the solid phase (formed using the particle midpoints) and the pore-phase. Structural characteristics rooted in the analysis of random point processes are seen to yield valuable insights into the underlying structure of granular...

Electrophorescing biopolymers across nanopores modulates the ionic current through the pore, revealing the polymer's diameter, length, and conformation. The rapidity of polymer translocation ( approximately 30,000 bp/ms) in this geometry greatly limits the information that can be obtained for each base. Here we show that the translocation speed of lambda-DNA through artificial nanopores can be ...

I consider a great lipid vesicle filled with an aqueous solution of a solute, for which its membrane is impermeable. Because of the mechanical tension induced by the osmotic flow, the vesicle swells up to a critical size, triggering a transient lipidic pore when it is introduced into a hypotonic aqueous medium. In this paper, we will obtain the differential equations of the vesicle dynamics, wh...

Inorganic polyphosphate (polyP) is a biopolymer of phosphoanhydride-linked orthophosphate residues. PolyP is involved in multiple cellular processes including mitochondrial metabolism and cell death. We used artificial membranes and isolated mitochondria to investigate the role of the polyP in mitochondrial ion transport and in activation of PTP. Here, we found that polyP can modify ion permeab...

The concept is easy to understand: A membrane with a single pore of appropriate size (diameter comparable to that of the molecule to detect) separates the two halves of an electrochemical cell. The cell is filled with an electrolyte, and a voltage is applied across the membrane. In the absence of any biomolecules in the solution, a steady flow of ions is measured as a constant current. As soon ...